1. Field of the Invention
The present invention relates to image processing for an image recording apparatus which records a color image on a recording medium.
2. Description of the Related Art
In general, a color printer is requested to have an ability to record a larger number of colors. As a technique for widening the color gamut and implementing good color development, the following techniques are known.
First, there is a technique using color materials of particular colors such as red, green, and blue, in addition to those of cyan, magenta, yellow, and black. This technique widens the red color region in the printer not by recording a dot of the magenta color material and that of the yellow color material to overlap each other, but by recording a dot of the red color material different in color development from these color materials.
Also, there is a technique of controlling the dot arrangement so that dots of color materials of particular colors do not overlap those of color materials of other colors as much as possible. If dots of particular colors overlap those of other colors, the color development of the particular colors is impaired. Hence, the dot arrangement is controlled so that these dots do not overlap each other, thereby avoiding the appearance of a dot arrangement with poor color development and implementing a wider color gamut.
However, the technique using color materials of particular colors inevitably increases the cost and apparatus size because additional color materials need to be mounted in the printer. The technique of controlling the dot arrangement cannot obtain the effect of widening the color gamut when the color development of a particular color itself is poor or when the color development of a dot (to be referred to as an “overlapping dot” hereinafter) at which a color material of a particular color and that of another color overlap each other is good.
Further, when a dot of a particular color and that of another color are arranged not to overlap each other, dots of other colors readily overlap each other. The color gamut may become narrow depending on the characteristics of the color material and recording medium.